The present invention relates to cleaning machines and, in particular, to cleaning machines having agitators for use in cleaning floors, carpets, upholstery and other surfaces.
Individuals often use cleaning machines, such as vacuum cleaners or carpet sweepers, to clean upholstery, floors and other surfaces and surface coverings. The typical cleaning machine has a base or head, such as a power nozzle on a vacuum cleaner, that is moved over the surface to be cleaned. In some cleaning machines, suction is provided which draws particles from a section of the surface being cleaned into the cleaning machine where the dirty air is passed through a bag in which the entrained particles are captured.
An agitator is often rotatably attached to the base or head to improve the effectiveness of the cleaning machine. The agitator typically has one or more projections that impinge on the surface being cleaned as the agitator rotates. A vacuum cleaner, for example, has a roller brush with bristles that brush the surface as the base or head is moved across the surface to be cleaned. As the vacuum cleaner moves over the surface, the roller brush rapidly rotates and the bristles repeatedly impinge on the surface. This contact between the bristles and the surface agitates dirt and other particles from the surface and improves the effectiveness of the vacuum cleaner. A carpet sweeper has a rotating blade that similarly impinges the surface being cleaned. An example of such a device is illustrated in U.S. Pat. No. 4,646,380.
The agitator typically rotates about an axle that rotates within a pair of bearings mounted either in the cleaning machine or in the agitator. The bearings allow the agitator to rotate with a minimal amount of resistance. A belt driven by a motor rotates the agitator when the motor is operating. The belt is wrapped around a pulley on the agitator and a pulley coupled to the motor. The rotational speed of the agitator is a function of the speed of the motor and the relative sizes of the two pulleys.
As the cleaning machine is moved over a surface, the projections on the agitator stir particles from the surface, which are collected by the cleaning machine. The projections also pick up elongated fibers, such as a string, carpet fibers or a strand of hair. The fibers can become wrapped around the agitator, and are thus not collected by the cleaning machine. If the fibers are not regularly removed from the agitator, the number of fibers wrapped around the agitator can increase to a point at which the effectiveness of the agitator decreases and can become damaged.
Users often can experience difficulty removing fibers from the agitator. Fibers are commonly removed from the agitator by hand, the user pulling on the end of the fibers and manually unrolling them from the agitator. Some users pull centrally on the fibers to partially separate them from the agitator, then cut or break the fibers and manually pull the smaller, cut pieces of fiber off of tile agitator. Removing fibers from the agitator can be a tedious task, as the fibers can be wrapped tightly around the agitator and difficult to grab. In addition, the fibers can be tangled and difficult to unwrap. In many cases, the user merely chooses not to remove the fibers from the agitatorxe2x80x94accepting the reduced effectiveness of and possibility of damage to the cleaning machine.
Fibers left on the agitator can work their way to the ends of the agitator and become wrapped around one or both of the end axles. Fibers wrapped around the axles are even more difficult to remove than fibers wrapped around the agitator. In many cases, the agitator must be removed from the cleaning machine before the fibers can be removed from the axles. Fibers wrapped around the axles can significantly increase the friction between the agitator and the cleaning machine. Those fibers that work their way to the ends of the agitator can also become enmeshed with the axle bearings, drive belt, and/or belt pulleys.
Increased friction between the agitator and the cleaning machine or the agitator drive mechanism can damage the cleaning machine or reduce its effectiveness. As the friction increases, the rotational speed of the agitator may decrease, lessening its agitating effect and straining the drive motor. As the friction further increases, brushes in the drive motor can burn out, or the belt can begin to slip on one or both of the pulleys. A slipping belt can wear down on the pulley until it breaks. Once the belt breaks, the agitator stops spinning and the effectiveness of the cleaning machine is reduced considerably or lost.
The present invention is directed toward agitators, such as roller brushes, for use with cleaning machines for cleaning upholstery, floors or other surfaces or surface coverings, and that are configured to facilitate the removal of elongated fibers therefrom, as well as methods for making the same.
In one embodiment of the present invention, a roller brush has a rotatable member with opposing first and second ends, an axis of rotation extending between the first and second ends, and an external surface extending at least partially between the first and second ends. A number of projections, such as bristles, are attached to the external surface of the agitator. One or both of the ends are configured to rotatably engage the cleaning machine, such as through a support bearing or other connector. The external surface of the rotatable member has a first portion that is substantially cylindrical about the axis of rotation, and a second portion spaced inwardly from the first portion to form a depression. The depression is configured to allow a user to insert a cutting tool partially into the depression and cut the fibers wrapped around the rotatable member. Once cut, the vacuum can be uprighted and turned on to vacuum up the cut fibers. The fibers may never need to be touched or disposed of by the user.